The invention relates to a device for gripping and tensioning ropes, cables and lines, particularly in sheet-winches, hoisting winches or windlasses, in tackles or pulley blocks by means of permanently or operationally interconnected coniform discs which can be actuated by motor or by hand via a crank or a tackle line and which exhibit surface contours producing sufficient retention force with only a single loop of the means of traction.
Similar devices are shown in DE 26 02 629 C3 and DE 25 52 436 C2. In these embodiments, the force transmitting organs, namely the ropes, cables or lines, are gripped by self-induced friction between coniform discs or by arrest of the transmitting means in order to ensure sufficient frictional force even with high loads if necessary, in a multiple winding around the drum as in DE 27 40 090 C2.
Other devices for retaining, drawing in or letting out cables of infinite or average length without winding the cable onto a drum are known. In these, means are provided to enable pulling the cable in both directions irrespective of its length. This purpose provides a running roller with a groove in which, through self-actuation, the cable is gripped by movable cheeks with the result that any length of the cable can be drawn in or let out. However, these cheeks make rapid looping of the tensioning means difficult, and moreover, the forces applied by one cheek are not always sufficient to arrest the cable adequately in the tensioning device. As a result of the relatively large tractive forces acting on the tensioning means the cheek is also subject to large pulling forces.
Furthermore, all profile designs known so far have the disadvantage that they are based on the principle of friction and do not grip reliably with a single loop, making additional loops to increase friction necessary. This undesirably increases the construction height of winches as in DE 27 40 090 C2, or effects considerable scuffing on the cable surface as in the profiles described in DE-GM 75 00 571.